1. Field of the Invention
The present invention relates to an imprint method used for manufacturing a device such as a semiconductor device element, an optical device element or a biological product.
2. Description of the Related Art
As a technique to manage both the formation of fine patterns of less than 100 nm and the mass-productivity in the manufacture of semiconductor device elements, nano-imprint technique has received attention by which a pattern of nano-imprint mold (also known as mold or template) is transferred on a substrate.
An optical (UV) nano-imprint is one of the nano-imprint techniques. The optical nano-imprint includes a step of applying light curable resin on a substrate, a step of aligning the nano-imprint mold with the substrate (alignment), a step of directly contacting the nano-imprint mold on the light curable resin (imprinting), a step of curing the light curable resin by irradiating the light curable resin with light, a step of separating (demolding) the nano-imprint mold from the cured light curable resin (mask) (Jpn. Pat. Appln. KOKAI Publication No. 2000-194142.).
Here, when a narrow and tall pattern, that is, a high aspect ratio of pattern is included in the cured light curable resin, a defect such as tear of the high aspect ration pattern may arise at the time of demolding. One reason for such the defect is that frictional force is generated between the cured light curable resin and the nano-imprint mold at the time demolding, and another reason is that the tensile strength of the cured light curable resin decreases as the pattern width narrows.